PROJECT SUMMARY This resubmission application requests continued funding for a postdoctoral research training program in hematology that has been successful in attracting young scientists and physician-scientists into academic careers in hematology and vascular biology. The program has as its primary objective to prepare MD, MD/PhD, and PhD postdoctoral fellows for productive careers as academic scientists and physician- scientists. The focus of training supported by this grant remains within the core scientific discipline of hematology. We are requesting support for four postdoctoral trainees per year (two PhD trainees and two MD or MD/PhD trainees), which is unchanged from the previous grant period. The training will be carried out in an enriched environment of active basic, translational and clinical investigation at an institution that emphasizes the career development and collaborative science. The specific objectives are: (1) To identify and recruit outstanding postdoctoral trainees, of diverse gender, ethnicity and culture, who wish to obtain comprehensive knowledge of the principles and techniques of basic and translational research related to hematology, blood cells, vascular biology, coagulation, hematopoiesis, and immunobiology; (2) To attract highly motivated scientists and physician-scientists and provide them with comprehensive instruction in the design and implementation of high quality research projects, including participation in cross-disciplinary research teams; (3) To train physician-scientists for academic careers in hematology and related scientific disciplines and prepare them for successful transition to independent investigators; and (4) To expose talented PhD scientists to the field of hematology and train them for careers as independent investigators and research scientists. Since the last renewal, several new initiatives have been instituted. The curriculum now includes core lectures in clinical hematology and required workshops in hematology research methods, rigor and reproducibility, and grant writing. Mentoring committees and individual development plans are required for all trainees. A structured mentoring plan for physician scientists has been developed since the previous submission. The foundation of training continues to be centered on the individual mentored research project, marked by a period of intensive, sustained research under the guidance of an established, dedicated mentor. This training is supplemented and enhanced by didactic and mentored training opportunities in team science and translational science, and by exposure to productive investigators working in related areas, including scientists with expertise in basic biomedical science, genomics, computational biology, and bioinformatics. The rich training environment provided by the diverse faculty, extensive laboratory, clinical, and core facilities, and strong institutional support should ensure continued success in attracting and preparing highly qualified postdoctoral trainees for careers in academic hematology.